Documentary Description
Veterinary scientist Mark Evans acts as guide as a team of experts
investigate the giraffe. Creationists question how this
extraordinary creature could have evolved such a long neck, but for
evolutionary biologist Professor Richard Dawkins the anatomy of the
world's tallest animal provides some of the best arguments in favour of
Darwinian natural selection. For example, one nerve takes a huge
detour up and down the long neck, from the voice box to the brain, via
the chest - hardly the work of an `Intelligent Designer'. And, despite
its length, the neck still only has seven vertebrae - the same number as
almost all mammals, from mice to humans and whales. But it's no
wonder the giraffe has the highest blood pressure of any animal; with a
heart not much bigger than our own it must pump blood at high pressure
around a towering body. It has evolved thick skin that acts as a natural
'G-suit' and a complex circulation system to avoid passing out when
raising and lowering its head. And as the dissection team piece
together the remarkable evolutionary story of the giraffe, biologist
Simon Watt observes them in the field as they eat, forage and fight.
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